Important Cura settings to make waterproof prints?

[TheMainMan 0]

What are some important changes from the default settings in Cura when printing a cup with PETG and a .4 mm nozzle to close all layer gaps so it can hold water without leaking?

[Slashee_the_Cow 619]

I'm not sure there's that many you can change other than making sure you have enough walls and skin layers.

Probably wouldn't hurt to turn up Top/Bottom > Skin Overlap (which makes it expand slightly into the walls.

And maybe turn up Material > Flow > Outer Wall Flow a bit (I'd start testing at 110%) to home some will ooze down just a little and help cover up any layer gaps (although if you have enough walls that should close up any potential gap).

 

And as always remember: small scale testing is your friend. Make a shot glass before you try a yard glass.

[SensataPDS 2]

You might want to use ironing on the top layers and maybe print the at a big layer height, less layers less gaps?

[Slashee_the_Cow 619]

9 hours ago, SensataPDS said:

You might want to use ironing on the top layers and maybe print the at a big layer height, less layers less gaps?

Ironing the top layer is just going to make it look pretty (although go for it if that's what you want). And I'm not saying go short (because there is such a thing as too short in this case) but while taller layers have fewer layer gaps, the gaps are going to be bigger and harder to cover by a method like increasing flow.